温馨提示：本站仅提供公开网络链接索引服务，不存储、不篡改任何第三方内容，所有内容版权归原作者所有
AI智能索引来源：http://www.edu.com/math-glossary/Plane-Shapes-Definition-Examples
点击访问原文链接

Plane Shapes – Definition, Examples | EDU.COM

进入原网站 导航首页
Plane Shapes – Definition, Examples | EDU.COMEDU.COMResourcesBlogGuidePodcastPlanBackHomesvg]:size-3.5">Math Glossarysvg]:size-3.5">Plane ShapesPlane Shapes – Definition, ExamplesTable of ContentsPlane Shapes Definition of Plane Shapes

Plane shapes, also known as two-dimensional shapes, are fundamental geometric figures that exist in a flat, two-dimensional plane. These shapes have length and width but no thickness or depth, unlike three-dimensional shapes, making them ideal for representation on a flat surface. Plane shapes can be defined by their boundaries, which can be made up of straight sides or curved lines. Examples include polygons (like triangles and quadrilaterals), circles, and other curvilinear figures.

In geometry, plane shapes can be categorized as open or closed based on their boundaries. Closed shapes have a complete boundary forming a closed loop, such as polygons and circles, which enclose a finite area. Open shapes have one or more breaks in their boundary and don't form a closed loop, like lines, line segments, and rays. Polygons, which are closed shapes with straight sides, can be further classified as regular or irregular, concave or convex, and simple or complex. The points where two sides meet in a polygon are called vertices or corners.

Examples of Plane Shapes Example 1: Identifying Non-Plane Shapes Problem:

Which of the following are not plane shapes? Circle, Sphere, Cube, Square, Triangle

plane shapes

Step-by-step solution:

Step 1, Look at each shape and decide if it is a plane shape (2D) or a solid shape (3D).

Step 2, Remember that plane shapes have only length and width, while solid shapes have length, width, and height (depth).

Step 3, Examine each shape:

Circle: Has only length and width, so it is a plane shape. Sphere: Has length, width, and depth (it's round like a ball), so it is a 3D shape. Cube: Has length, width, and depth (it's like a box), so it is a 3D shape. Square: Has only length and width, so it is a plane shape. Triangle: Has only length and width, so it is a plane shape.

Step 4, Make the final list of non-plane shapes: Sphere and cube are 3D shapes, so they are not plane shapes.

Example 2: Identifying Closed Shapes Problem:

Which of the following is not an open shape?

plane shapes

Step-by-step solution:

Step 1, Remember that open shapes have endpoints that don't connect, while closed shapes form a complete loop with no open ends.

Step 2, Look at each shape carefully:

Shape a: Has different starting and end points, so it is an open shape. Shape b: Has different starting and end points, so it is an open shape. Shape c: Has different starting and end points, so it is an open shape. Shape d: Has no open ends and forms a complete loop, so it is a closed shape.

Step 3, Find which shape is not open: Shape d is not an open shape because it forms a closed loop and has an interior.

Example 3: Counting Sides and Vertices Problem:

How many sides and vertices does this shape have? Is the shape closed or open? plane shapes

Step-by-step solution:

Step 1, Count the number of straight line segments in the shape. Each straight line counts as one side.

Step 2, Looking at the shape, we can count 8 straight lines connected to each other. This makes it an octagon (an 8-sided polygon).

Step 3, The vertices are the points where the sides meet. Since each side connects to another side at a point, an octagon has 8 vertices.

Step 4, Check if the shape is closed or open by seeing if you can trace the outline without lifting your pencil and return to the starting point.

Step 5, Since this octagon's outline can be traced without any gaps, it is a closed shape.

Comments(6)MMovieBuffCameronNovember 4, 2025I've used this plane shapes def for my kid's study. It's super clear. Helped them grasp 2D shapes in no time!

MCMs. CarterSeptember 17, 2025I’ve been using this page to help my kids understand plane shapes, and it’s been so helpful! The examples make it easy to explain the difference between open and closed shapes. Great resource!

MCMs. CarterSeptember 10, 2025I used the Plane Shapes definition and examples from this page to help my kids with their homework, and it worked great! The clear explanations and examples made it so easy for them to understand. Thanks for this resource!

MCMs. CarterAugust 27, 2025I’ve been using this page to teach my kids about plane shapes, and it’s been such a helpful resource! The examples make it super easy for them to understand the difference between open and closed shapes. Highly recommend!

NNatureLover85August 20, 2025I used the Plane Shapes definition and examples to help my kids understand 2D shapes better. The clear explanations and classifications made it so easy for them to grasp! Highly recommend this resource for parents and teachers.

svg]:px-3 dk:w-auto h-10 dk:h-14 rounded-lg dk:rounded-[15px] px-5 dk:px-7.5 text-sm dk:text-xl text-[#3467FF] bg-white hover:bg-white">Load MoreExplore More TermsBracesCardinal NumbersNumber SentenceNumerical ExpressionAreaFactor TreeView All Math TermsRecommended Interactive LessonsMultiply by 63Math3.OA.C.7Understand Unit Fractions on a Number Line3Math3.NF.A.2a， 3.NF.A.Find the Missing Numbers in Multiplication Tables3Math3.OA.D.9Multiply by 33Math3.OA.C.7Use Arrays to Understand the Distributive Property3Math3.OA.B.5Understand Non-Unit Fractions on a Number Line3Math3.NF.A.1View All Interactive LessonsRecommended VideosCompare Numbers to 10KMathK.CC.C.7Describe Positions Using In Front of and BehindKMathK.G.A.1Use Models to Subtract Within 1002Math2.NBT.B.5Area And The Distributive Property3Math3.MD.C.7.cWord Problems: Multiplication3Math3.OA.A.3Use Dot Plots to Describe and Interpret Data Set6Math6.SP.B.4, 6.SP.B.5a, 6.SP.B.5b, 6.SP.B.5c, 6.SP.A.2View All VideosRecommended WorksheetsUse The Standard Algorithm To Add With Regrouping1Math1.NBT.C.4Count on to Add Within 201Math1.OA.C.5, 1.OA.C.6Use A Number Line To Subtract Within 1002Math2.NBT.B.5Arrays and division3Math3.OA.A.2Use Models and Rules to Multiply Whole Numbers by Fractions5Math5.NF.B.4aMeasures Of Center: Mean, Median, And Mode6Math6.SP.A.2, 6.SP.A.3, 6.SP.B.5cView All WorksheetsRecommended Coloring PagesA heart-shaped puzzle with a teddy bear holding a piecePre-K – KAll SubjectsLarge upper and lower case letter O with an onion with a happy face beside itPre-K – KAll SubjectsSimple tree branch with a few blossomsPre-K – KAll SubjectsLetter M with a monkey swinging on a vine above it, with jungle leaves in the background1 – 2All SubjectsEaster egg with stripes and flowers surrounding it1 – 2All SubjectsApple tree with a ladder leaning against it and a person climbing to pick apples3 – 4All SubjectsView All Coloring PagesRecommended Blogs25 Hilarious Middle School Memes That Every K-6 Teacher Will Relate ToSeptember 17, 2025Funny Math Memes That Make Learning Addition and Subtraction a Blast for K-6 StudentsSeptember 17, 202523 Powerful Proverbs Related to Education That Transform Learning in K-6 ClassroomsSeptember 17, 202550 Heartwarming Kindness Quotes to Transform Your Classroom and HomeSeptember 17, 2025Powerful Graduation Inspirational Quotes to Motivate K-6 Students and FamiliesSeptember 17, 2025School Memes: How Humor Helps Teachers and Kids Navigate the Emotional Ups and Downs of LearningSeptember 17, 2025View All Blog PostsQUICK LINKSAbout UsPrivacy PolicyTerms of ServiceTOOLSHomework HelperGuide DesignerPodcast MakerPlan BuilderRESOURCESMath GlossaryEnglish GlossaryEnglish Language ArtsMathematicsScienceBook InsightsFun with WordsBlog© 2025 EDU.COM. All rights reserved.

智能索引记录